std::experimental::ranges::reference_t, std::experimental::ranges::rvalue_reference_t, std::experimental::ranges::iter_common_reference_t
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                    < cpp | experimental | ranges
                    
                                                            
                    | Defined in header  <experimental/ranges/iterator> | ||
| template< class T > concept bool /*dereferenceable*/ = requires(T& t) { {*t} -> auto&&; }; | (exposition only*) | |
| template< /*dereferenceable*/ T >  using reference_t = decltype(*declval<T&>()); | (1) | (ranges TS) | 
| template< /*dereferenceable*/ T >     requires requires(T& t) { { ranges::iter_move(t) } -> auto&&; } | (2) | (ranges TS) | 
| template< Readable T >  using iter_common_reference_t = ranges::common_reference_t<ranges::reference_t<T>, | (3) | (ranges TS) | 
1) Obtain the reference type of a dereferenceable type 
T.2) Obtain the rvalue reference type of a dereferenceable type 
T, that is, the return type of ranges::iter_move.3) Compute a 
Readable type's common reference type. This is the common reference type of its reference type and an lvalue reference to its value type.[edit] Notes
The -> auto&& constraint checks that the type of the expression is not void.


